7.5: Origin of the Solar System
By the end of this section, you will be able to:
- Describe the characteristics of planets that are used to create formation models of the solar system
- Describe how the characteristics of extrasolar systems help us to model our own solar system
- Explain the importance of collisions in the formation of the solar system
Much of astronomy is motivated by a desire to understand the origin of things: to find at least partial answers to age-old questions of where the universe, the Sun, Earth, and we ourselves came from. Each planet and moon is a fascinating place that may stimulate our imagination as we try to picture what it would be like to visit. Taken together, the members of the solar system preserve patterns that can tell us about the formation of the entire system. As we begin our exploration of the planets, we want to introduce our modern picture of how the solar system formed.
The recent discovery of thousands of planets in orbit around other stars has shown astronomers that many exoplanetary systems can be quite different from our own solar system. For example, it is common for these systems to include planets intermediate in size between our terrestrial and giant planets. These are often called superearths . Some exoplanet systems even have giant planets close to the star, reversing the order we see in our system. In The Birth of Stars and the Discovery of Planets outside the Solar System, we will look at these exoplanet systems. But for now, let us focus on theories of how our own particular system has formed and evolved.
Looking for Patterns
One way to approach our question of origin is to look for regularities among the planets. We found, for example, that all the planets lie in nearly the same plane and revolve in the same direction around the Sun. The Sun also spins in the same direction about its own axis. Astronomers interpret this pattern as evidence that the Sun and planets formed together from a spinning cloud of gas and dust that we call the solar nebula (Figure 7.17).
The composition of the planets gives another clue about origins. Spectroscopic analysis allows us to determine which elements are present in the Sun and the planets. The Sun has the same hydrogen-dominated composition as Jupiter and Saturn, and therefore appears to have been formed from the same reservoir of material. In comparison, the terrestrial planets and our Moon are relatively deficient in the light gases and the various ices that form from the common elements oxygen, carbon, and nitrogen. Instead, on Earth and its neighbors, we see mostly the rarer heavy elements such as iron and silicon. This pattern suggests that the processes that led to planet formation in the inner solar system must somehow have excluded much of the lighter materials that are common elsewhere. These lighter materials must have escaped, leaving a residue of heavy stuff.
The reason for this is not hard to guess, bearing in mind the heat of the Sun. The inner planets and most of the asteroids are made of rock and metal, which can survive heat, but they contain very little ice or gas, which evaporate when temperatures are high. (To see what we mean, just compare how long a rock and an ice cube survive when they are placed in the sunlight.) In the outer solar system, where it has always been cooler, the planets and their moons, as well as icy dwarf planets and comets, are composed mostly of ice and gas.
The Evidence from Far Away
A second approach to understanding the origins of the solar system is to look outward for evidence that other systems of planets are forming elsewhere. We cannot look back in time to the formation of our own system, but many stars in space are much younger than the Sun. In these systems, the processes of planet formation might still be accessible to direct observation. We observe that there are many other “solar nebulas” or circumstellar disks —flattened, spinning clouds of gas and dust surrounding young stars. These disks resemble our own solar system’s initial stages of formation billions of years ago (Figure 7.18).
Building Planets
Circumstellar disks are a common occurrence around very young stars, suggesting that disks and stars form together. Astronomers can use theoretical calculations to see how solid bodies might form from the gas and dust in these disks as they cool. These models show that material begins to coalesce first by forming smaller objects, precursors of the planets, which we call planetesimals .
Today’s fast computers can simulate the way millions of planetesimals, probably no larger than 100 kilometers in diameter, might gather together under their mutual gravity to form the planets we see today. We are beginning to understand that this process was a violent one, with planetesimals crashing into each other and sometimes even disrupting the growing planets themselves. As a consequence of those violent impacts (and the heat from radioactive elements in them), all the planets were heated until they were liquid and gas, and therefore differentiated, which helps explain their present internal structures.
The process of impacts and collisions in the early solar system was complex and, apparently, often random. The solar nebula model can explain many of the regularities we find in the solar system, but the random collisions of massive collections of planetesimals could be the reason for some exceptions to the “rules” of solar system behavior. For example, why do the planets Uranus and Pluto spin on their sides? Why does Venus spin slowly and in the opposite direction from the other planets? Why does the composition of the Moon resemble Earth in many ways and yet exhibit substantial differences? The answers to such questions probably lie in enormous collisions that took place in the solar system long before life on Earth began.
Today, some 4.5 billion years after its origin, the solar system is—thank goodness—a much less violent place. As we will see, however, some planetesimals have continued to interact and collide, and their fragments move about the solar system as roving “transients” that can make trouble for the established members of the Sun’s family, such as our own Earth. (We discuss this “troublemaking” in Comets and Asteroids: Debris of the Solar System.)
A great variety of infographics at space.com let you explore what it would be like to live on various worlds in the solar system.


17.1: Preface
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I am writing these words on a sheet of white paper, with a (cheap, disposable) fountain pen. By the time you read what I am writing, however, it will have been transformed. First, I will transfer it by a different set of bodily actions (typing on a keyboard) and through the software on my computer to convert it into a string of 1s and 0s. I will then send it through the ether to the editors who will, in turn, submit it in a similar digital form to the publisher. The publisher will use the digital file to produce a paper version, in essentially the same way that books have been produced for over 500 years, since the development of the printing press (in Europe) by Johannes Gutenberg. The chances are that you are now reading this in a form familiar for half a millennium, although you might well be viewing it on a digital device, again translated by that device’s software into an arrangement of black and white pixels that mimics the printed page. Such are the processes of writing and reading in the second decade of the 21 st century...
How to cite this book chapter:
Bennet, J. 2013. Epilogue. In: Piquette, K. E. and Whitehouse, R. D. (eds.)
Writing as Material Practice: Substance, surface and medium.
Pp. 335-342. London: Ubiquity Press. DOI: http:// dx.doi.org/10.5334/bai.q


2.2: Physical Development
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Growth in Early Childhood
Children between the ages of 2 and 6 years tend to grow about 3 inches in height each year and gain about 4 to 5 pounds in weight each year. The average 6 year old weighs about 46 pounds and is about 46 inches in height. The 3 year old is very similar to a toddler with a large head, large stomach, short arms and legs. But by the time the child reaches age 6, the torso has lengthened and body proportions have become more like those of adults.
This growth rate is slower than that of infancy and is accompanied by a reduced appetite between the ages of 2 and 6. This change can sometimes be surprising to parents and lead to the development of poor eating habits.
Nutritional Concerns
Caregivers who have established a feeding routine with their child can find this reduction in appetite a bit frustrating and become concerned that the child is going to starve. However, by providing adequate, sound nutrition, and limiting sugary snacks and drinks, the caregiver can be assured that 1) the child will not starve; and 2) the child will receive adequate nutrition. Preschoolers can experience iron deficiencies if not given well-balanced nutrition and if given too much milk. Calcium interferes with the absorption of iron in the diet as well.
Caregivers need to keep in mind that they are setting up taste preferences at this age. Young children who grow accustomed to high fat, very sweet and salty flavors may have trouble eating foods that have more subtle flavors such as fruits and vegetables. Consider the following advice about establishing eating patterns for years to come (Rice, F.P., 1997). Notice that keeping mealtime pleasant, providing sound nutrition and not engaging in power struggles over food are the main goals:
Tips for Establishing Healthy Eating Patterns
- Don’t try to force your child to eat or fight over food. Of course, it is impossible to force someone to eat. But the real advice here is to avoid turning food into some kind of ammunition during a fight.
- Recognize that appetite varies. Children may eat well at one meal and have no appetite at another. Rather than seeing this as a problem, it may help to realize that appetites do vary. Continue to provide good nutrition, but do not worry excessively if the child does not eat.
- Keep it pleasant. This tip is designed to help caregivers create a positive atmosphere during mealtime. Mealtimes should not be the time for arguments or expressing tensions. You do not want the child to have painful memories of mealtimes together or have nervous stomachs and problems eating and digesting food due to stress.
- No short order chefs. While it is fine to prepare foods that children enjoy, preparing a different meal for each child or family member sets up an unrealistic expectation from others. Children probably do best when they are hungry and a meal is ready. Limiting snacks rather than allowing children to “graze” continuously can help create an appetite for whatever is being served.
- Limit choices. If you give your preschool aged child choices, make sure that you give them one or two specific choices rather than asking “What would you like for lunch?” If given an open choice, children may change their minds or choose whatever their sibling does not choose!
- Serve balanced meals. This tip encourages caregivers to serve balanced meals. A box of macaroni and cheese is not a balanced meal. Meals prepared at home tend to have better nutritional value than fast food or frozen dinners. Prepared foods tend to be higher in fat and sugar content as these ingredients enhance taste and profit margin because fresh food is often more costly and less profitable. However, preparing fresh food at home is not costly. It does, however, require more activity. Preparing meals and including the children in kitchen chores can provide a fun and memorable experience.
- Don’t bribe. Bribing a child to eat vegetable by promising desert is not a good idea. For one reason, the child will likely find a way to get the desert without eating the vegetables (by whining or fidgeting, perhaps, until the caregiver gives in), and for another reason, because it teaches the child that some foods are better than others. Children tend to naturally enjoy a variety of foods until they are taught that some are considered less desirable than others. A child, for example, may learn the broccoli they have enjoyed is seen as yucky by others unless it’s smothered in cheese sauce!
To what extent do these tips address cultural practices? How might these tips vary by culture?
Brain Maturation
Brain weight: If you recall, the brain is about 75 percent its adult weight by two years of age. By age 6, it is at 95 percent its adult weight. Myelination and the development of dendrites continues to occur in the cortex and as it does, we see a corresponding change in what the child is capable of doing. Greater development in the prefrontal cortex, the area of the brain behind the forehead that helps us to think, strategizes, and controls emotion, makes it increasingly possible to control emotional outbursts and to understand how to play games. Consider 4 or 5 year old children and how they might approach a game of soccer. Chances are every move would be a response to the commands of a coach standing nearby calling out, “Run this way! Now, stop. Look at the ball. Kick the ball!” And when the child is not being told what to do, he or she is likely to be looking at the clover on the ground or a dog on the other side of the fence! Understanding the game, thinking ahead, and coordinating movement improve with practice and myelination. Not being too upset over a loss, hopefully, does as well.
Visual Pathways
Have you ever examined the drawings of young children? If you look closely, you can almost see the development of visual pathways reflected in the way these images change as pathways become more mature. Early scribbles and dots illustrate the use of simple motor skills. No real connection is made between an image being visualized and what is created on paper.
At age 3, the child begins to draw wispy creatures with heads and not much other detail. Gradually pictures begin to have more detail and incorporate more parts of the body. Arm buds become arms and faces take on noses, lips and eventually eyelashes. Look for drawings that you or your child has created to see this fascinating trend. Here are some examples of pictures drawn by my daughters from ages 2 to 7 years.
Growth in the hemispheres and corpus callosum: Between ages 3 and 6, the left hemisphere of the brain grows dramatically. This side of the brain or hemisphere is typically involved in language skills. The right hemisphere continues to grow throughout early childhood and is involved in tasks that require spatial skills such as recognizing shapes and patterns. The corpus callosum which connects the two hemispheres of the brain undergoes a growth spurt between ages 3 and 6 as well and results in improved coordination between right and left hemisphere tasks. (I once saw a 5 year old hopping on one foot, rubbing his stomach and patting his head all at the same time. I asked him what he was doing and he replied, “My teacher said this would help my corpus callosum!” Apparently, his kindergarten teacher had explained the process!)
Motor Skill Development : Early childhood is a time when children are especially attracted to motion and song.  Even the booth at a restaurant affords the opportunity to slide around in the seat or disappear underneath and imagine being a sea creature in a cave! Of course, this can be frustrating to a caregiver, but it’s the business of early childhood. Children continue to improve their gross motor skills as they run and jump. And frequently ask their caregivers to “look at me” while they hop or roll down a hill. Children’s songs are often accompanied by arm and leg movements or cues to turn around or move from left to right. Fine motor skills are also being refined in activities such as pouring water into a container, drawing, coloring, and using scissors. Some children’s songs promote fine motor skills as well (have you ever heard of the song “itsy, bitsy, spider”?). Mastering the fine art of cutting one’s own fingernails or tying shoes will take a lot of practice and maturation. Motor skills continue to develop in middle childhood-but for preschoolers, play that deliberately involves these skills is emphasized.
Go ahead. Sing along and practice your fine motor skills.
Sexual Development in Early Childhood
Historically, children have been thought of as innocent or incapable of sexual arousal (Aries, 1962). Yet, the physical dimension of sexual arousal is present from birth. But to associate the elements of seduction, power, love, or lust that is part of the adult meanings of sexuality would be inappropriate. Sexuality begins in childhood as a response to physical states and sensation and cannot be interpreted as similar to that of adults in any way (Carroll, 2007).
Infancy: Boys and girls are capable of erections and vaginal lubrication even before birth (Martinson, 1981). Arousal can signal overall physical contentment and stimulation that accompanies feeding or warmth. And infants begin to explore their bodies and touch their genitals as soon as they have the sufficient motor skills. This stimulation is for comfort or to relieve tension rather than to reach orgasm (Carroll, 2007).
Early Childhood: Self-stimulation is common in early childhood for both boys and girls. Curiosity about the body and about others’ bodies is a natural part of early childhood as well. Consider this example.  The mother hesitates a bit and then responds, “Yes. I think that’s alright.” “Hmmm,” the girl begins, “When I grow up, I want to be a doctor!” Hopefully, this subject is approached in a way that teaches children to be safe and know what is appropriate without frightening them or causing shame.
As children grow, they are more likely to show their genitals to siblings or peers, and to take off their clothes and touch each other (Okami et al., 1997). Masturbation is common for both boys and girls. Boys are often shown by other boys how to masturbate. But girls tend to find out accidentally. And boys masturbate more often and touch themselves more openly than do girls (Schwartz, 1999).
Hopefully, parents respond to this without undue alarm and without making the child feel guilty about their bodies. Instead, messages about what is going on and the appropriate time and place for such activities help the child learn what is appropriate.


6.4: Resistance
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The concept of resistance is most likely familiar to readers via Ohm’s Law for Devices ; i.e., \(V=IR\) where \(V\) is the potential difference associated with a current \(I\). This is correct, but it is not the whole story. Let’s begin with a statement of intent:
Resistance \(R\) (\(\Omega\)) is a characterization of the conductivity of a device (as opposed to a material ) in terms of Ohms Law for Devices; i.e., \(V=IR\).
Resistance is a property of devices such as resistors , which are intended to provide resistance, as well as being a property of most practical electronic devices, whether it is desired or not.
Resistance is a manifestation of the conductivity of the materials comprising the device, which subsequently leads to the “\(V=IR\)” relationship. This brings us to a very important point and a common source of confusion. Resistance is not necessarily the real part of impedance. Let’s take a moment to elaborate. Impedance (\(Z\)) is defined as the ratio of voltage to current; i.e., \(V/I\); or equivalently in the phasor domain as \(\widetilde{V}/\widetilde{I}\). Most devices – not just devices exhibiting resistance – can be characterized in terms of this ratio. Consider for example the input impedance of a terminated transmission line (Section 3.15). This impedance may have a non-zero real-valued component even when the transmission line and the terminating load are comprised of perfect conductors. Summarizing:
Resistance results in a real-valued impedance. However, not all devices exhibiting a real-valued impedance exhibit resistance. Furthermore, the real component of a complex-valued impedance does not necessarily represent resistance.
Restating the main point in yet other words: Resistance pertains to limited conductivity, not simply to voltage-current ratio.
Also important to realize is that whereas conductivity \(\sigma\) (units of S/m) is a property of materials, resistance depends on both conductivity and the geometry of the device. In this section, we address the question of how the resistance of a device can be is determined. The following example serves this purpose.
Figure \(\PageIndex{1}\) shows a straight wire of length \(l\) centered on the \(z\) axis, forming a cylinder of material having conductivity \(\sigma\) and cross-sectional radius \(a\). The ends of the cylinder are covered by perfectly-conducting plates to which the terminals are attached. A battery is connected to the terminals, resulting in a uniform internal electric field \({\bf E}\) between the plates.
Figure \(\PageIndex{1}\): Analysis of the resistance of straight wire of circular cross-section. ( CC BY SA 4.0 ; K.Kikkeri).To calculate \(R\) for this device, let us first calculate \(V\), then \(I\), and finally \(R=V/I\). First, we compute the potential difference using the following result from Section 5.8:
\[V = -\int_{\mathcal C}{\bf E}\cdot d{\bf l} \nonumber \]
Here we can view \(V\) as a “given” (being the voltage of the battery), but wish to evaluate the right hand side so as to learn something about the effect of the conductivity and geometry of the wire. The appropriate choice of \({\mathcal C}\) begins at \(z=0\) and ends at \(z=l\), following the axis of the cylinder. (Remember: \({\mathcal C}\) defines the reference direction for increasing potential, so the resulting potential difference will be the node voltage at the end point minus the node voltage at the start point.) Thus, \(d{\bf l} = \hat{\bf z}dz\) and we have
\[V = - \int _ { z = 0 } ^ { l } \mathbf { E } \cdot ( \hat { \mathbf { z } } d z ) \nonumber \]
We do not yet know \({\bf E}\); however, we know it is constant throughout the device and points in the \(-\hat{\bf z}\) direction since this is the direction of current flow and Ohm’s Law for Electromagnetics (Section 6.3) requires the electric field to point in the same direction. Thus, we may write \({\bf E}=-\hat{\bf z}E_z\) where \(E_z\) is a constant. We now find:
\begin{aligned} V & = - \int _ { z = 0 } ^ { l } \left( - \hat { \mathbf { z } } E _ { z } \right) \cdot ( \hat { \mathbf { z } } d z ) \\ & = + E _ { z } \int _ { z = 0 } ^ { l } d z \\ & = + E _ { z } l \end{aligned}
The current \(I\) is given by (Section 6.2)
\[I=\int_{\mathcal{S}} \mathbf{J} \cdot d \mathbf{s} \nonumber \]
We choose the surface \(\mathcal{S}\) to be the cross-section perpendicular to the axis of the wire. Also, we choose \(d{\bf s}\) to point such that \(I\) is positive with respect to the sign convention shown in Figure \(\PageIndex{1}\). With these choices, we have From Ohm’s Law for Electromagnetics, we have
\[{\bf J} = \sigma{\bf E} = -\hat{\bf z} \sigma E_z \nonumber \]
So now
\[\begin{aligned} I & = \int _ { \rho = 0 } ^ { a } \int _ { \phi = 0 } ^ { 2 \pi } \left( - \hat { \mathbf { z } } \sigma E _ { z } \right) \cdot ( - \hat { \mathbf { z } } \rho d \rho d \phi ) \\ & = \sigma E _ { z } \int _ { \rho = 0 } ^ { a } \int _ { \phi = 0 } ^ { 2 \pi } \rho d \rho d \phi \\ & = \sigma E _ { z } \left( \pi a ^ { 2 } \right) \end{aligned} \nonumber \]
Finally:
\[R = \frac{V}{I} = \frac{E_z l}{\sigma E_z \left( \pi a^2 \right)} = \frac{l}{\sigma \left( \pi a^2 \right)} \nonumber \]
This is a good-enough answer for the problem posed, but it is easily generalized a bit further. Noting that \(\pi a^2\) in the denominator is the cross-sectional area \(A\) of the wire, so we find:
\[\boxed{ R = \frac{l}{\sigma A} } \label{m0071_eRwireDC} \]
i.e., the resistance of a wire having cross-sectional area \(A\) – regardless of the shape of the cross-section, is given by the above equation.
The resistance of a right cylinder of material, given by Equation \ref{m0071_eRwireDC}, is proportional to length and inversely proportional to cross-sectional area and conductivity.
It is important to remember that Equation \ref{m0071_eRwireDC} presumes that the volume current density \({\bf J}\) is uniform over the cross-section of the wire. This is an excellent approximation for thin wires at “low” frequencies including, of course, DC. At higher frequencies it may not be a good assumption that \({\bf J}\) is uniformly-distributed over the cross-section of the wire, and at sufficiently high frequencies one finds instead that the current is effectively limited to the exterior surface of the wire. In the “high frequency” case, \(A\) in Equation \ref{m0071_eRwireDC} is reduced from the physical area to a smaller value corresponding to the reduced area through which most of the current flows. Therefore, \(R\) increases with increasing frequency. To quantify the high frequency behavior of \(R\) (including determination of what constitutes “high frequency” in this context) one requires concepts beyond the theory of electrostatics, so this is addressed elsewhere.
Example \(\PageIndex{1}\):Resistance of 22 AWG hookup wire
A common type of wire found in DC applications is 22AWG (“American Wire Gauge”; see “Additional Resources” at the end of this section) copper solid-conductor hookup wire. This type of wire has circular cross-section with diameter 0.644 mm. What is the resistance of 3 m of this wire? Assume copper conductivity of \(58\) MS/m.
Solution
From the problem statement, the diameter \(2a=0.644\) mm, \(\sigma=58\times 10^6\) S/m, and \(l=3\) m. The cross-sectional area is \(A=\pi a^2 \cong 3.26\times10^{-7}\) m\(^2\). Using Equation \ref{m0071_eRwireDC} we obtain \(R=159\) m\(\Omega\).
Example \(\PageIndex{2}\): Resistance of steel pipe
A pipe is 3 m long and has inner and outer radii of 5 mm and 7 mm respectively. It is made from steel having conductivity 4 MS/m. What is the DC resistance of this pipe?
Solution
We can use Equation \ref{m0071_eRwireDC} if we can determine the cross-sectional area \(A\) through which the current flows. This area is simply the area defined by the outer radius, \(\pi b^2\), minus the area defined by the inner radius \(\pi a^2\). Thus, \(A = \pi b^2 - \pi a^2 \cong 7.54 \times 10^{-5}\) m\(^2\). From the problem statement, we also determine that \(\sigma=4\times 10^6\) S/m and \(l=3\) m. Using Equation \ref{m0071_eRwireDC} we obtain \(R \cong 9.95\) m\(\Omega\).


6.1: Products of Groups
In this section, we will discuss a method for using existing groups as building blocks to form new groups.
Suppose \((G,*)\) and \((H,\odot)\) are two groups. Recall that the Cartesian product of \(G\) and \(H\) is defined to be \[G\times H=\{(g,h)\mid g\in G,h\in H\}\] Using the binary operations for the groups \(G\) and \(H\) , we can define a binary operation on the set \(G\times H\) . Define \(\star\) on \(G\times H\) via \[(g_1,h_1)\star(g_2,h_2)=(g_1*g_2,h_1\odot h_2).\] This looks fancier than it is. We’re just doing the operation of each group in the appropriate component. It turns out that \((G\times H,\star)\) is a group.
Suppose \((G,*)\) and \((H,\odot)\) are two groups, where \(e\) and \(e'\) are the identity elements of \(G\) and \(H\) , respectively. Then \((G\times H,\star)\) is a group, where \(\star\) is defined as above. Moreover, \((e,e')\) is the identity of \(G\times H\) and the inverse of \((g,h)\in G\times H\) is given by \((g,h)^{-1}=(g^{-1},h^{-1})\) .
We refer to \(G\times H\) as the direct product of the groups \(G\) and \(H\) . In this case, each of \(G\) and \(H\) is called a factor of the direct product. We often abbreviate \((g_1,h_1)\star(g_2,h_2)=(g_1*g_2,h_1\odot h_2)\) by \((g_1,h_1)(g_2,h_2)=(g_1 g_2,h_1 h_2)\) . One exception to this is if we are using the operation of addition in each component. For example, consider \(\mathbb{Z}_4\times \mathbb{Z}_2\) under the operation of addition mod 4 in the first component and addition mod 2 in the second component. Then \[\mathbb{Z}_4 \times \mathbb{Z}_2=\{(0,0),(1,0),(2,0),(3,0),(0,1),(1,1),(2,1),(3,1)\}.\] In this case, we will use additive notation in \(\mathbb{Z}_4\times \mathbb{Z}_2\) . For example, in \(\mathbb{Z}_4 \times \mathbb{Z}_2\) we have \[(2,1)+(3,1)=(1,0)\] and \[(1,0)+(2,1)=(3,1).\] Moreover, the identity of the group is \((0,0)\) . As an example, the inverse of \((1,1)\) is \((3,1)\) since \((1,1)+(3,1)=(0,0)\) . There is a very natural generating set for \(\mathbb{Z}_4\times \mathbb{Z}_2\) , namely, \(\{(1,0),(0,1)\}\) since \(1\in \mathbb{Z}_4\) and \(1\in \mathbb{Z}_2\) generate \(\mathbb{Z}_4\) and \(\mathbb{Z}_2\) , respectively. The corresponding Cayley diagram is given in Figure \(\PageIndex{1}\).
Consider the group \(\mathbb{Z}_4 \times \mathbb{Z}_2\) . Is this group abelian? Is the group cyclic? Determine whether \(\mathbb{Z}_4 \times \mathbb{Z}_2\) is isomorphic to any of \(D_4\) , \(Q_8\) , \(\mathbb{Z}_8\) , or \(L_3\) .
The upshot of the previous problem is that there are at least five groups of order 8 up to isomorphism. It turns out that there are exactly five groups of order 8 up to isomorphism. In particular, every group of order 8 is isomorphic to one of the following groups: \(\mathbb{Z}_8\) , \(\mathbb{Z}_4 \times \mathbb{Z}_2\) , \(L_3\) , \(D_4\) , and \(Q_8\) . Note that \(R_8\cong \mathbb{Z}_8\) and \(\text{Spin}_{1\times 2}\cong D_4\) . Three of the isomorphism classes correspond to abelian groups while the other two correspond to non-abelian groups. Unfortunately, we will not develop the tools necessary to prove that this classification is complete.
The next two theorems should not be terribly surprising.
If \(G_1\) and \(G_2\) are groups, then \(G_1\times G_2\cong G_2\times G_1\) .
Suppose \(G_1\) and \(G_2\) are groups with identities \(e_1\) and \(e_2\) , respectively. Then \(\{e_1\}\times G_2\cong G_2\) and \(G_1\times \{e_2\}\cong G_1\) .
There’s no reason we can’t take the direct product of more than two groups. If \(A_1, A_2, \ldots, A_n\) is a collection of sets, we define \[\prod_{i=1}^nA_i:=A_1\times A_2\times \cdots \times A_n.\] Each element of \(\prod_{i=1}^nA_i\) is of the form \((a_1,a_2,\ldots, a_n)\) , where \(a_i\in A_i\) .
Let \(G_1, G_2,\ldots, G_n\) be groups. For \((a_1,a_2, \ldots, a_n), (b_1,b_2,\ldots, b_n)\in \prod_{i=1}^nG_i\) , define \[(a_1,a_2, \ldots, a_n)(b_1,b_2,\ldots, b_n)=(a_1b_1,a_2b_2,\ldots, a_nb_n).\] Then \(\prod_{i=1}^nG_i\) , the direct product of \(G_1,\ldots, G_n\) , is a group under this binary operation.
One way to think about direct products is that we can navigate the product by navigating each factor simultaneously but independently. Computing the order of a group that is a direct product is straightforward.
Let \(G_1, G_2,\ldots, G_n\) be finite groups. Then \[|G_1\times G_2\times \cdots \times G_n|=|G_1|\cdot|G_2|\cdots |G_n|.\]
Let \(G_1, G_2,\ldots, G_n\) be groups. Then \(|G_1\times G_2\times \cdots \times G_n|\) is infinite if and only if at least one \(|G_i|\) is infinite.
The following theorem should be clear.
Let \(G_1, G_2,\ldots, G_n\) be groups. Then \(\prod_{i=1}^nG_i\) is abelian if and only if each \(G_i\) is abelian.
Let’s play with a few more examples.
Draw the Cayley diagram for \(\mathbb{Z}_2\times \mathbb{Z}_3\) using \(\{(1,0),(0,1)\}\) as the generating set. Is \(\mathbb{Z}_2\times \mathbb{Z}_3\) an abelian group? Is it cyclic? What familiar group is \(\mathbb{Z}_2\times \mathbb{Z}_3\) isomorphic to?
Consider \(\mathbb{Z}_2\times \mathbb{Z}_2\) under the operation of addition mod 2 in each component. Find a generating set for \(\mathbb{Z}_2\times \mathbb{Z}_2\) and then create a Cayley diagram for this group. What well-known group is \(\mathbb{Z}_2\times \mathbb{Z}_2\) isomorphic to?
Consider the similarities and differences between \(\mathbb{Z}_2\times \mathbb{Z}_3\) and \(\mathbb{Z}_2\times \mathbb{Z}_2\) . Both groups are abelian by Theorem \(\PageIndex{7}\), but only the former is cyclic. Here’s another exercise.
Consider the group \(\mathbb{Z}_2 \times \mathbb{Z}_2 \times \mathbb{Z}_2\) . Find a generating set for \(\mathbb{Z}_2 \times \mathbb{Z}_2 \times \mathbb{Z}_2\) and then create a Cayley diagram for this group. Is there a group that we have seen before that \(\mathbb{Z}_2 \times \mathbb{Z}_2 \times \mathbb{Z}_2\) isomorphic to?
The next theorem tells us how to compute the order of an element in a direct product of groups.
Suppose \(G_1, G_2,\ldots, G_n\) are groups and let \((g_1,g_2,\ldots, g_n)\in \prod_{i=1}^nG_i\) . If \(|g_i|=r_i<\infty\) , then \(|(g_1,g_2,\ldots, g_n)|=\text{lcm}(r_1,r_2,\ldots,r_n)\) .
Find the order of each of the following elements.
- \((6,5)\in\mathbb{Z}_{12}\times \mathbb{Z}_7\) .
- \((r,i)\in D_3\times Q_8\) .
- \(((1,2)(3,4),3)\in S_4\times \mathbb{Z}_{15}\) .
Find the largest possible order of elements in each of the following groups.
- \(\mathbb{Z}_6\times \mathbb{Z}_8\)
- \(\mathbb{Z}_9\times \mathbb{Z}_{12}\)
- \(\mathbb{Z}_4\times \mathbb{Z}_{18}\times \mathbb{Z}_{15}\)
The group \(\mathbb{Z}_m\times \mathbb{Z}_n\) is cyclic if and only if \(m\) and \(n\) are relatively prime.
The group \(\mathbb{Z}_m\times \mathbb{Z}_n\) is isomorphic to \(\mathbb{Z}_{mn}\) if and only if \(m\) and \(n\) are relatively prime.
The previous results can be extended to more than two factors.
The group \(\prod_{i=1}^n \mathbb{Z}_{m_i}\) is cyclic and isomorphic to \(\mathbb{Z}_{m_1m_2\cdots m_n}\) if and only if every pair from the collection \(\{m_1,m_2,\ldots, m_n\}\) is relatively prime.
Determine whether each of the following groups is cyclic.
- \(\mathbb{Z}_7\times \mathbb{Z}_8\)
- \(\mathbb{Z}_7\times \mathbb{Z}_7\)
- \(\mathbb{Z}_2\times \mathbb{Z}_7\times \mathbb{Z}_8\)
- \(\mathbb{Z}_5\times \mathbb{Z}_7\times \mathbb{Z}_8\)
Suppose \(n=p_1^{n_1}p_2^{n_2}\cdots p_r^{n_r}\) , where each \(p_i\) is a distinct prime number. Then \[\mathbb{Z}_n\cong \mathbb{Z}_{p_1^{n_1}}\times \mathbb{Z}_{p_2^{n_2}}\times \cdots \times \mathbb{Z}_{p_r^{n_r}}.\]
The next theorem tells us that the direct product of subgroups is always a subgroup.
Suppose \(G_1\) and \(G_2\) are groups such that \(H_1\leq G_1\) and \(H_2\leq G_2\) . Then \(H_1\times H_2\leq G_1\times G_2\) .
However, not every subgroup of a direct product has the form above.
Find an example that illustrates that not every subgroup of a direct product is the direct product of subgroups of the factors.
Can we extend Theorem \(\PageIndex{12}\) to normal subgroups? That is, if \(H_1\trianglelefteq G_1\) and \(H_2\trianglelefteq G_2\) , is it the case that \(H_1\times H_2\trianglelefteq G_1\times G_2\) ? If so, prove it. Otherwise, provide a counterexample.
The next theorem describes precisely the structure of finite abelian groups. We will omit its proof, but allow ourselves to utilize it as needed.
Every finitely generated abelian group \(G\) is isomorphic to a direct product of cyclic groups of the form \[\mathbb{Z}_{p_1^{n_1}}\times \mathbb{Z}_{p_2^{n_2}}\times \cdots \times \mathbb{Z}_{p_r^{n_r}}\times \mathbb{Z}^k,\] where each \(p_i\) is a prime number (not necessarily distinct). The product is unique up to rearrangement of the factors.
Note that the number \(k\) is called the Betti number . A finitely generated abelian group is finite if and only if the Betti number is 0.
Find all abelian groups up to isomorphism of order 8. How many different groups up to isomorphism (both abelian and non-abelian) have we seen and what are they?
Find all abelian groups up to isomorphism for each of the following orders.
- 16
- 12
- 25
- 30
- 60


11.4: Environmental Issues
Environmental issues are effects of human activity on the biophysical environment, most often of which are harmful effects that cause environmental degradation. Due to the dynamic range of environments found in California, environmentalism has been an important part of California's history since it became a US state. However, this history is more complex than you might expect. While California is home to abundant resources noted for their pristine quality, the resources must support the most populous state in the US. The struggle between respecting the natural beauty of the state and providing for the basic needs of its inhabitants has defined a great amount of California's past, just as it still defines California and likely will far into the future. Environment destruction caused by humans is a global, ongoing problem. Major current environmental issues may include climate change, drought, pollution, environmental degradation, and resource depletion.
Drought
Although drought is a common feature in a natural Mediterranean Climate, data shows that California can has had some very extreme droughts. Out of the past twenty-two years, California has experienced significant drought conditions for thirteen years. From 2000 to 2018 was the second driest period that California has ever experienced. The driest three-year period ever in California was from 2012 to 2014. Three-quarters of the state of California experienced extreme drought conditions. There are also multiple types of droughts such as agricultural droughts, meteorological droughts, snow droughts, and hydrological droughts. All these affect California in different ways. Droughts can damage forests and can worsen wildfires by drying the trees, which become fuel for fires. Dead trees result in wildfires. The U.S. drought monitor is released every Thursday, showing which parts of the U.S. are in a drought. It started in 2000, and since then the longest duration of a drought in California lasted a total of 376 weeks. It started on December 11, 2011 and ended on March 5, 2019. The most intense period captured on the drought monitor was on the week of July 29, 2014. It showed that 58.41% of California's land was affected by a drought. In 2014–2015, farm-related losses in California totaled $5 billion and 20,000 farmers also lost their jobs.
Air Pollution
Air pollution is a growing problem that affects all the citizens in the Central Valley. Some reasons of poor air pollution in the Central Valley are due to agriculture and its geographical features.
Since the Central Valley consists mostly of farming land, a wide, flat valley, the emissions from the soil that is used for growing produce are released into the air. The soil exudes nitrous oxide, an odorless and colorless gas that can be harmful when exposed to it for a long period of time, and incorporates itself into the ozone layer located at ground level. Production of nitrous oxide in California has shown that the addition of soil and fertilization can emit about 161,100 metric tons per year.
The physical geographical attributes can also contribute to the air pollution quality. The Central Valley is surrounded by mountain ranges which can capture the pollution coming from the agricultural farming, preventing it from dispersing from the other areas in California.
The Central Valley is also expanding in the number of people that coincide in that area, so it increases the number of cars which can also contribute to the amount of emission that is in the air.
Health Geography
The valley gives its name to Valley Fever, which is primarily a disease of the lungs that is common in the southwestern United States and northwestern Mexico. It is caused by the fungus Coccidioides immitis , which grows in soils in areas of low rainfall, high summer temperatures, and moderate winter temperatures. These fungal spores become airborne when the soil is disturbed by winds, construction, farming, or earthquakes. This illness frequently takes weeks or months to resolve. Occasionally Valley Fever is life-threatening or even fatal. Due to the agricultural industry's significant presence in the Valley, pesticide drift and leaching have become concerns. Residents risk contamination when living in proximity to application sites.
Economic Geography - Agriculture
The Central Valley is one of the world's most productive agricultural regions. More than 230 crops are grown there. On less than 1 percent of the total farmland in the United States, the Central Valley produces 8 percent of the nation's agricultural output by value: US$43.5 billion in 2013. California's farms and ranches earned almost $50 billion in 2018. The valley's productivity relies on irrigation from surface water and badly depleted underground aquifers. About one-sixth of the US' irrigated land is in the Central Valley.
Virtually all non-tropical crops are grown in the Central Valley, which is the primary source for produce throughout the United States, including tomatoes, grapes, cotton, apricots, and asparagus. Six thousand almond growers produced more than 600 million pounds (in 2000, about 70 percent of the world's supply and nearly 100 percent of domestic production.
The US' top four counties in agricultural sales are in the Central Valley
- Fresno County - $3.7 Billion
- Tulare County - $3.3 Billion
- Kern County - $3.2 Billion
- Merced County - $2.3 Billion
Early farming was concentrated close to the Sacramento-San Joaquin Delta, where the water table was high year-round and water transport was readily available. Subsequent irrigation projects brought many more parts of the valley into productive use. The even larger California State Water Project was formed in the 1950s and construction continued over the following decades.


9.2: Events, Participants, and Thematic Roles
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A YouTube element has been excluded from this version of the text. You can view it online here: https://ecampusontario.pressbooks.pub/essentialsoflinguistics/?p=199
Check Yourself
1. What label best describes the thematic role of the underlined NP?
The guard chased the intruder.
- Agent.
- Theme.
- Cause.
- Instrument.
- Location.
- Experiencer.
2. What label best describes the thematic role of the underlined NP?
The wind slammed the door shut.
- Agent.
- Theme.
- Cause.
- Instrument.
- Location.
- Experiencer.
3. What label best describes the thematic role of the underlined NP?
The guard followed the intruder .
- Agent.
- Theme.
- Cause.
- Instrument.
- Location.
- Experiencer.
Video Script
We’ve spent a lot of time thinking about the structure of sentences. We’re now turning our attention to what sentences mean. Sentences usually describe events or states in the world. And events usually have participants: the people or things that play a role in the event. Usually, noun phrases are used to refer to the participants in an event. It turns out that, even across events that are quite different from each other, some participants share some elements of meaning.
Take a look at the underlined phrases in each of these sentences.
Mina tore the wrapping paper.
Sam ran a marathon.
The students studied for their exam.
Neeraja waited for the bus.
Carlos ate the rice.
We can see that the grammatical role of each of these is a subject: They’re all in the specifier of TP. Semantically, the events that each sentence describes are quite different: tearing is different from running which is different from studying or waiting or eating. But even across these different events, the participants described by the underlined noun phrases all share some semantic similarities: all of them choose to take part in the event, all of them are causing the event to happen. Let’s look at another few sentences.
Mina tore the wrapping paper.
A nail tore her skirt.
The fabric tore.
All of these sentences have the same verb and they all describe a tearing event. And all the underlined phrases have the grammatical role of subject, but they don’t share the same semantic properties. In the first sentence, Mina is the one who causes the tearing event to happen: you can imagine her gleefully tearing the paper open to see what’s inside. In the second sentence, the nail is sort of responsible for the tearing, but it certainly doesn’t choose to make it happen. And in the third sentence, the fabric is the thing that the tearing happens to, not the participant that makes the tearing happen. So even though all three of these NPs are subjects, they don’t all share semantic properties.
Remember that we use grammatical roles to label the syntactic position of a noun phrase in a sentence. We’re now going to introduce a new kind of label, called thematic roles . We can use thematic roles to identify common semantic properties of the participants in events. An important thing to notice about thematic roles is that they are independent of grammatical roles. In this pair of sentences,
Kavitha cooked this lovely meal.
This lovely meal was cooked by Kavitha.
the grammatical role for Kavitha is different: Kavitha is the subject of one sentence but an oblique in the other. But semantically, Kavitha’s role in the cooking event is the same in both sentences. We say that Kavitha’s thematic role is the agent .
The kinds of participants that we label as agents tend to have three properties: usually, they are volitional , meaning they choose to participate in the event. They’re sentient , that is, they’re aware of the event, and often they’re the ones that bring the event about or cause it to take place. Let’s look back at that tearing event.
Mina tore the paper.
The paper tore.
Again in these sentences, the paper has two different grammatical roles: it’s the direct object in the first sentence but the subject of the second, but semantically its role as a participant in the tearing event is the same in both: it’s the thing that the tearing happens to. Its thematic role is called a theme , or in some books, you’ll see it called a patient . Theme participants typically undergo events, that is, events happen to them. They’re affected by events, and often they change state or position as a result of an event.
Take a minute and try to think of some sentences that describe events that have agent and theme participants. They’re probably the two most common thematic role labels, and in fact, one theory of semantics says that every participant is either an Agents or Themes, just to a greater or lesser degree. But it can also be useful to have labels for some other kinds of participants, and the grammars of many languages encode other semantic properties besides those two.
Some languages make a morphological distinction between an animate agent and an inanimate cause . In a sentence like, The hurricane destroyed the houses ., the hurricane is clearly responsible for the destroying event, but it’s not sentient or volitional — the hurricane isn’t choosing to bring about the destroying. Likewise, in The movie frightened the children , the movie isn’t really a typical agent. We label these inanimate participants with the label cause A cause participant shares the agentive property of causing an event to happen, but it’s not aware of the event and doesn’t choose to cause it, because the cause is inanimate.
In this sentence, The knife cut the bread, would you say that the knife is a cause participant? Certainly, the knife is inanimate, and it’s not aware of the cutting event, but it’s also not really causing the cutting to happen, is it? There’s some unnamed agent who must be using the knife to cut the bread. We could label the knife as an instrument . An instrument is the participant that an agent uses to make an event happen.
Many languages have special morphology to indicate the location of an event, like in these sentences:
The Habs won the game at the Forum .
The kids ran through the sprinkler on the lawn .
The parade travelled around the neighbourhood .
The noun phrases the forum , the lawn and the neighbourhood all have the thematic role of location .
So we’ve got labels like cause , instrument , and location to describe some of the roles that inanimate participants typically have in events. I want to return to animate participants to look at one more important role. Let’s look at the human participants in these sentences:
Phoebe tripped on the curb.
Sun-Jin won the lottery.
The movie frightened Farah .
If Phoebe tripped on the curb, it doesn’t seem quite right to label Phoebe as an agent — presumably, she didn’t choose to trip on the curb, even if she is aware of it, and she isn’t really the cause of the tripping event; the curb is. And no matter how badly you might want to win the lottery, you can’t really cause it to happen, so Sun-Jin isn’t a great example of an agent either. Likewise, if we say that the movie frightened Farah, Farah isn’t exactly a theme; yes, the frightening is happening to her, but she’s not necessarily changed by it, and she is aware of the event.
Let’s label these participants with the thematic role of the experiencer . Experiencers are like the middle ground between agents and themes. They are animate and sentient, so they’re aware of events happening, but they don’t necessarily choose or cause events to happen; events happen to them. Because experiencers have this in-between status, they can show up either as subjects or as objects, like in these examples:
The children were scared of the clowns.
The clowns frightened the children .
And we could say that Phoebe and Sun-Jin are experiencers of their tripping and winning events: they don’t cause the events to happen, but they are aware of the events happening.
To sum up, thematic role labels capture the semantic properties of participants in events, independent of the syntactic position of the noun phrase. Just because something has the grammatical role of a subject doesn’t mean it will necessarily have the thematic role of agent and vice versa. There’s a fair amount of argument in the literature about exactly how many thematic role labels are necessary to capture the relevant patterns of behaviour in the languages of the world, with proposals ranging from two to about fifteen thematic roles. We’ll settle on the middle ground and use six thematic role labels:
- Agent
- Theme
- Cause
- Instrument
- Location
- Experiencer


1.3: The Internet, Cloud Computing, and the Internet of Things
By the end of this section, you will be able to:
- Explain how the internet has evolved and how it functions in today’s world
- Describe how to conduct an effective internet search
- Conduct business research on the internet
- Explain the use of cloud computing for business
- Define the Internet of Things
The internet has dramatically transformed how we access and manage information, both at home and in the business world. For many people, it’s almost impossible to go about your day without needing access to the internet. It’s in your home—from smart doorbells to TVs, thermostats, and personal assistants. It’s on your wrist, in your car, and, of course, on your phone. It’s big business and it is integral to just about every business out there.
Established businesses have taken advantage of the ability to reach new customers by selling their products online, while would-be entrepreneurs use the internet to open online storefronts. The internet also enables us to conduct both personal and professional transactions more efficiently—from accessing important health-care documents to filing our tax returns, transferring money between bank accounts, and making payments to individuals online. Many of us practically run our lives through our phones.
Read this article on the invention of the internet to learn more. When was the internet first developed and for what purpose? How did it evolve into the internet we use today?
The Internet: From Inception to Today
The internet as we know it today originated in the 1960s with the idea of using a traditional telephone switching circuit to wirelessly connect computers in a network. The telephone system would allow these computers to communicate with one another, exchange data, and run shared programs. Researchers and engineers from both the public and the private sector came together to form the Advanced Research Projects Agency (ARPA) to investigate ways the U.S. military could improve communications, with the goal of protecting the country from unexpected enemy attacks.
In 1969, a new digital packet switching technology was introduced to enable two computers to communicate with each other, replacing the telephone circuit technology. Packet switching happens when computers break down data or information into smaller groups (packets) and transmit several of those packets over the network. When the packets reach the destination computer, they are put back together in their original form. The communication occurred through the traditional phone line system but was transformed into digital data during transmission. The packet technology did not require a dedicated telephone line to network the computers together. This was the origin of the ARPA Network , or ARPANET , and is the same technology used today for the internet. The networked computers were also able to send simple messages to one another, setting the stage for email as we know it today. Figure 1.22 shows an early iteration of the ARPA network.
In less than five years, the network expanded to include thirty different organizations and institutions across the world, and by 1975, ARPA determined that it needed to establish standards for consistency. These rules helped ensure that the interconnected network, or internet, was secure and efficient. The transmission control protocol/internet protocol (TCP/IP) was established to standardize the computer language used between the computers in the network. With these rules, a unique internet protocol address (IP address) allowed users to determine the geographic location of any computer on the network. The IP address was also used to direct the transmitted information to the appropriate destination. Because the IP address is a series of numbers and decimal points that can be hard to remember, the domain name system (DNS) was developed in 1983 to convert IP addresses into simple names. The DNS thus became the phone book for the internet, enabling users to send a message using their name, the symbol @, and the location of the computer as identified by its domain name. With the DNS, the foundation of the World Wide Web (WWW) was put into place. The term internet simply refers to the interconnected computers, a network that now extends across the world. The WWW is the content that has been collected over the internet and is available online. By 1981, the network had grown to over 200 hosts. The first domain name was registered in 1985 to a computer manufacturer.
By the mid-1980s, scientists and researchers across the world were working on computer networking technology. With the success of the ARPANET, the ARPA group was charged with working on other, more cutting-edge projects. The ARPANET-connected organizations were predominantly government entities or educational research centers; the system was not available for commercial or personal use. Consequently, the project was moved to the U.S. Department of Defense, where the network continued to expand through various branches, including NASA and the National Science Foundation (NSF). In 1985, the NSF created the structure for a supercomputing center to connect colleges and universities, research centers, and regional networks. By the end of the 1980s, this network had grown to over 30,000 hosts. As a result, ARPANET was decommissioned in 1990.
In 1989, the first dial-up internet service provider (ISP) was established, allowing commercial access to the internet. The term dial-up internet emerged to describe how users would use existing telephone technology to “dial up” internet access through a specific provider. Because the internet was established primarily for military use, access to the technology was highly restricted, limited to specific uses such as research. By 1992, Congress had allowed the NSF to grant some access to the network for uses beyond education and research. Then, in 1995, all restrictions on noncommercial uses of the internet were lifted.
In these early days, a good deal of computer knowledge was needed in order to use the network, so the internet was not yet part of mainstream life. But that was about to change. In 1990, hypertext transfer protocol (HTTP) , hypertext markup language (HTML) , and the uniform resource locator (URL) were developed to give the average person access to the web of information. This really was the birth of the World Wide Web. HTML provides the structure on which web pages are based; it is a series of commands that describe attributes such as the font size and background colors of the displayed page. The uniform resource locator (URL) is an address—similar to a postal address—that directs the user to a unique location or page on the World Wide Web. These two developments, along with the milestones shown in Figure 1.23 made the web less technically complex and easier for the average person to navigate.
People soon began to see the ease with which web pages could be created. In 1993, the first user-friendly web browser , Mosaic , came on the scene. A web browser provides the interface that you can use to search for the information stored on the WWW. Marc Andreessen, a student at the University of Illinois, developed it. One key feature of Mosaic was the ability to include images as well as text on a web page. Other features included buttons to select for navigating the page, the ability to include video clips, and hyperlinks. A hyperlink is a link that can take the user from one web page to another just by clicking the highlighted link. Initially available as a free download, Mosaic quickly caught on and evolved as more users came on board. Prior to Mosaic, fewer than 200 web pages were available, but in just a few short years by the late 1990s, that number grew to more than 100,000. After graduating, Andreessen formed Netscape Communications and would eventually launch Netscape Navigator , which would grow to over 10 million users globally in just two years. Microsoft was quick to respond with its browser, Internet Explorer , which was bundled with the Windows operating system.
HTML is used to create web pages. The information is contained behind the scenes and is used to format text and the layout of the page. Read this article about HTML and the process used to learn more. Watch this video on how HTML is used to build websites to learn more.
By 1998, some big tech names established themselves as internet-based businesses—Hotmail, Amazon, Google, eBay, and Yahoo!, to name a few. The rise of the internet led to what became known as the dot-com bubble , a period when investors poured money into many internet-based ventures that promised high returns. Of course, many of these ventures failed, and their investors lost a good deal of capital. But, despite this, new ideas continued to emerge, and the internet continued to grow. Here are a few internet ventures that came out of the dot-com bubble and are still around today:
- Wikipedia —2001
- Facebook —2004
- YouTube —2005
- Twitter (now X) —2006
- Hulu —2007
Having access to the internet is almost essential to fully participate in society today. In some instances, without the internet, even routine tasks can seem impossible. For example, some companies can be contacted only via the internet, so you may need internet access to even apply for a job. Because of the global nature of the internet, it might be assumed that everyone has access in some way. But even in the United States, there are large disparities in access to reliable internet connections. In today’s electronic world, this is furthering the gap between economic, racial, and ethnic groups; age groups; and socioeconomic groups. It is estimated that on average, nearly 15 percent of households in the United States with school-age children lack access to the internet. But in rural or low-income areas, this percentage could be much higher.
Governments are introducing initiatives to make the internet more accessible to all, often through partnerships with technology firms. For example, in a partnership with Google, the city of Austin, Texas, has been able to provide free internet services for nearly 2,000 lower-income residents. As early as 2006, India established internet access in its rural communities through the use of kiosks. These are just a couple of examples of the efforts worldwide to make the internet more accessible for all.
Using the Internet
Using the internet today is much simpler than it was even as recently as five years ago. It simply entails going to the web browser of our choice and clicking the mouse to launch it. Common browsers in use today include Google Chrome , Apple Safari , Microsoft Edge , and Firefox . The browser , once opened, will take you to where you want to go online. You can go directly to a web page by typing its URL in the navigation bar at the top of the browser. However, many browsers have a default search engine that will automatically launch when you open the browser and will allow you to search the internet for content you want to locate or research. Chrome, for example, will automatically navigate to the Google search engine when you open the Chrome program. Most browsers include a bookmark feature, and it may be helpful to bookmark/favorite pages that you visit frequently or want to remember for quick access later. With Chrome, you will see a star on the right-hand side of the URL to select to bookmark/favorite the page. Figure 1.24 shows these buttons.
Conducting Effective Searches
Conducting searches on the internet is straightforward, but there are some techniques that will make your searches more effective. Because of the vast amount of information available on the internet, incorporating some simple changes to your search strategies can make a huge difference. You might, for example, want to narrow the number of results that you get from a search to those that are most relevant. When you begin to type in a search term, most engines will display a list of suggested searches. This list of suggestions will give you similar, related searches using the terms that you have begun to type into the search bar. This is often helpful as you try to narrow your search to obtain the desired results, as Figure 1.25 shows.
As you conduct your search, it is often helpful to keep a list of search terms that you have successfully used. It is easy to forget that you have already used a particular phrase or word, so a simple list will make it easier to avoid replicating something you have already searched.
For example, suppose your boss at WorldCorp has asked you to search for a local nonprofit organization centered on children to support this year during the holidays. You might choose to search using the word or phrase children, kids, not for profit, nonprofit, or children in need, as just a few examples.
Search engines also offer the capability to search with an image or with voice instead of text. Once you have entered a search term or phrase, you have some additional options. For example, you can restrict the search to a certain date range or a certain location, or you can change the search to focus only on shopping related to your search term. See Figure 1.26. Keep in mind that once you reach a website, you will often find a search bar within the website itself. This will enable you to search within that specific website instead of conducting a search of the entire internet. A little trick for searching on a page is to use the control (Ctrl) key and the F key at the same time ( Ctrl+F ). When you press these two keys at the same time, a search window will appear that allows you to search on that specific web page.
To search within a web page on a Mac, type Command+F .
To conduct an internet search , it is best to use specific and unique terms whenever possible. For example, when searching for contact information for a nonprofit organization in your hometown, rather than simply using the term “food bank,” you should use the actual name of the food bank you are searching. Or, if you are unsure of the name of the organization, you might limit the search by combining “food bank” with the name of your town or city. You can add a phrase as well. Being more specific in your searches will lead to more refined results.
In defining your search, avoid using common words such as “a” and “the,” as well as punctuation marks. Also note that most search engines are not case sensitive, so proper capitalization is unimportant. Finally, to get the most results, it may be helpful to focus on the base or root word. For example, instead of searching on “running gear for women,” you might get more results by using “run gear women,” leaving the search open to words such as “runner” in addition to “running.”
Your internet searches can be further refined by adding “+” or “–” in front of a word to either add to the search term or exclude something from the term. If, for example, you are searching for theaters but do not want movie theaters, you can type “theater–movie” to get search results that do not include movie theaters. This same approach can be used with “+” to add more terms to your searches. (Note: Some search engines may use NOT or AND instead of the mathematical sign.)
To search for an exact phrase or string of words, enclose the phrase in quotation marks. For example, if you are looking for information about historic theaters, you can search by typing “historic theaters” and then perhaps add a location (city or state) at the end, also in quotation marks, so your search would be “historic theaters” “Atlanta.”
Use the tilde (~) to search for synonyms for the word you type. For example, searching “~coat” might return search results including jackets and sweatshirts. The asterisk (*) can be used to search partial words. This can be very helpful if you want to search for a specific person or location but are not sure of the correct spelling or the complete term. If you are researching nonprofit organizations and want to capture information that might just say “nonprofits” instead of the complete phrase, you can search using “nonprofit*.” Finally, the “|” or OR operator can search on two terms at the same time, giving you results for either of the two terms. Searching “black shoes for sale” | “brown shoes for sale” will return results that satisfy both search phrases. These operators can be combined in various ways to make your searches much more directed. Be careful not to be too restrictive, however, as you might filter out some relevant results. Table 1.1 summarizes the key internet search operators .
| Operator | Description |
|---|---|
| + , AND | Include a word in the search |
| –, NOT | Exclude a word from the search |
| “ ” | Search for the exact words contained between the quotation marks |
| * | Search partial words |
| ~ | Search for synonyms |
| |, OR | Search two words at the same time |
Conducting Business Research
Conducting business research via the internet enables you to access information quickly at little or no cost. The internet gives you access to a large body of data from a variety of sources across the world. There are both free and fee-based services available on the internet to gather data. In addition, you can access many academic, peer-reviewed research using specialized databases. The first step is to narrow your search by determining what information you need and making a list of the data needed. As you work through your search, be sure to record relevant search terms, the website URL, and other pertinent information for you to access later if needed. A good strategy might be to keep a notepad by the computer or keep an electronic record in Microsoft Word or Google Docs.
Some common sources of information for business research can be readily accessed:
- Google Scholar is a search engine for peer-reviewed academic research. Here, you will find journal articles (often full-text .pdf files) for nearly all disciplines. This source can be handy if you are looking for targeted information based on a specific academic discipline.
- Microsoft has a similar search engine called Microsoft Academic .
- Science.gov is a website that provides access to data from nearly twenty U.S. federal agencies.
- Census.gov is an excellent source of demographic information.
- If you are searching for financial information for companies, Yahoo! Finance or Google Finance is a great place to start.
- More detailed information about specific industries and sectors is available at CSImarket.com.
When conducting research on the internet, there always will be some question of the credibility of the information you find. Because virtually anyone can create a website or post information on the internet, you should read with a critical eye. There is a wealth of quality information available, but it is just as easy to stumble upon unreliable data. Wikipedia is a commonly searched source for information. Wikipedia is an online encyclopedia built organically by users (it isn’t owned by a person or organization). It was founded in 2001 as a nonprofit organization with the goal of giving free access to information for everyone. Wikipedia is the fifth most visited site on the internet. Users submit content to pages and check one another for accuracy. They are given guidelines to follow for fact checking and editorial changes. In most cases, however, using Wikipedia as the primary source for research is frowned upon because of the lack of authentic reliability checks for the information.
With any research, it is good practice to use triangulation : To verify the credibility of a piece of research, you should find at least three sources that are in agreement. By using multiple sources, you are minimizing the risk of uncertainty of the information found. It is also good practice to follow additional guidelines when evaluating the credibility of information found on the internet. By looking a little deeper into the research, you may uncover some hidden biases or questionable conclusions that were not readily apparent.
- Who is the author and what is their affiliation?
- Who paid for the research?
- What is the date of the information?
- Has the website been updated recently, and do the hyperlinks work?
- Are any clear biases or opinions expressed?
- Is there a way to contact the author or request more information?
By taking the time to dive a little deeper into the information retrieved, you can better ensure the data is credible and suitable for your needs.
Globalization
The internet has broken down many geographic barriers. Business transactions can easily happen from points across the globe, products can be ordered and efficiently shipped to destinations thousands of miles away, and individuals can readily access information related to current events in other countries. The global nature of the internet has opened up the world, but there is little consistency between countries in their management of this technology. There are distinct differences from country to country in the laws and regulations governing internet use. For example, Facebook and Google are banned in some countries, such as Iran and North Korea, because these sites are seen as contradictory to local traditions and customs. In China, the government plays a major role in monitoring what citizens can access and view on the internet. There are nearly 100 regulations specifically centered on the internet and its use in China.
Internet regulations across the world generally fall into one of four categories:
- Encouragement of self-regulation and voluntary use of filters for illegal material
- Punitive actions for making material available online that is unsuitable for children
- Required blocking of government-selected materials
- Prohibition on public access to the internet
Many countries have enacted some type of legislation, policy, or governmental oversight with the goal of managing internet content. This governmental involvement began as early as 1996 and continues to be amended today. As you enter the workplace, you should be aware of the specific legislation that might impact the industry that you are working in. This could include protecting user information through specific privacy controls to managing content on a social media site for appropriateness. You do not have to be a legal expert, but having a general awareness of governmental involvement in the information shared over the internet is important.
Communication, Collaboration, and Social Media
Through the internet and the software programs available today, we can stay connected to colleagues and family across great distances. Email, the Google Workspace of programs, Microsoft 365, and social media sites have all had a significant impact on business and personal productivity. Email first became a reality with the ARPANET. Today, we have many options when it comes to our email service. Gmail from Google and Outlook by Microsoft led the email market. These programs are directly integrated into their other products to aid in communication and collaboration between users. The enhanced capabilities of email programs today allow easy sharing of photos, documents, video, and large files. Just the ability to connect to colleagues who are outside of your general geographic area on a regular basis greatly improves productivity and connectivity.
We also now have several options for videoconferencing . Many people use these tools outside the workplace to spend time with out-of-town family and friends. The traditional telephone conference call where several people sit around a conference table while another colleague calls in on a speaker phone is a rare sight in today’s office. Now, we can gather around a virtual table and use a videoconferencing program to conduct an important business meeting (Figure 1.27). We can use the same program to have a virtual meal with a family member who lives miles away. Some of the leading videoconferencing tools today include Zoom , Microsoft Teams , Skype , WebEx , and Google Meet . All have basically the same functionality, with features such as recording the meeting and providing a transcript of the discussion. These features have been valuable as part of a widespread shift to remote working conditions for many companies. The shift to greater use of remote working environments occurs for various reasons, ranging from global issues such as a public health emergency to more localized reasons like increasing employee satisfaction by assisting in work/life balance.
Another tool people use to connect and collaborate with others is social media . Social media is digital technology that allows users (individuals and organizations) to share information about themselves such as posts, photos, or videos. More than 40 percent of the global population use social media. Social media sites had their origin in connecting friends and families. However, as the number of users increased, businesses started to see the value in connecting with their customers via these social media sites. Many businesses have a distinct presence on social media as active users, not simply advertising through the site. Today, about 70 percent of businesses have a social media presence. The line between personal and business has blurred significantly. Very few people use social media solely for connecting and sharing with friends and family. Most will interact with businesses such as retail outlets and even banks on their social media sites. Many people follow a specific brand or company that they like. Personal and business social media sites are intertwined and connected across sites.
This phenomenon has shifted how businesses manage relationships with their customers. Many banks, for example, have a social media site where they share financial tips and banking products/promotions available to their customers. Consumer products companies can use the sites to get feedback on product attributes or advertising strategies. Small businesses can use social media sites to offer promotions to bring more foot traffic into the store—whether online or brick-and-mortar.
The leading social media sites vary by age to some extent, with older generations leaning more toward Facebook and LinkedIn while younger people tend to gravitate to platforms such as TikTok , Instagram , Snapchat , and X (Twitter) . Other popular social media sites include Pinterest and Reddit .
Privacy is a concern when dealing with any interaction on the internet, but especially with social media sites, where individuals often share personal information and pictures that could open them up to cyberattacks. You should regularly check and update the privacy settings on the social media sites you use. You might consider changing your password routinely to prevent hackers from accessing your information. Never share personal information through the site or through messages within the site. You should be wary of friend/follower requests from people who are unknown to you or your other connections. Avoid being controversial or posting overly personal content. Employers now are checking applicants’ social media profiles and, in some cases, monitoring employees’ activity.
Finally, as a user, it is easy to get pulled into clicking on advertisements that either show up in the margins or in the social media feed. Clicking leaves a virtual footprint of your activity that both legitimate advertisers and spammers can use to target advertisements and compel you to visit their sites. Often, you can limit your exposure through the site privacy settings, but the risk of exposure of personal information probably cannot be totally mitigated unless you avoid using social media sites altogether.
Personally identifiable information (PII) may include items that directly reveal your identity, such as your address or Social Security number. But other identifiable information can also be gathered, such as race, gender, or religion. You should be cautious when sharing information on the internet via social media and other websites. Useful precautions include regularly changing your passwords, not using the same passwords for multiple sites, providing limited personal information on social media sites or putting privacy settings at a high level, and, finally, being cautious about clicking links or advertisements from unknown sources.
Libraries and Media
The internet has changed the way that libraries operate and store/share information. Many libraries still house extensive collections of books, reference materials, magazines, and the like. In fact, you may be surprised to learn that reading print books still outpaces reading electronic books. Some college students have reaped the benefits of e-books by purchasing their textbooks in (often cheaper) electronic formats. Unlike a traditional print copy of the same material, these textbooks are interactive, enabling the publisher to include updated information and links to relevant extra materials that cannot be included in the print edition. With the availability of the internet and today’s technology, students can also rent electronic textbooks, which can save a good deal of money over time. Currently, electronic textbooks hold about 30 percent of the total market.
Many libraries now have online services that allow users to place a hold on materials. When the item becomes available, the patron is notified via text or email. Libraries are also moving some of their resources to a digital format. For example, some of the historical archives housed in libraries have been cataloged digitally to provide broader access. Libraries will still have a good supply of DVDs or books on CD for patrons to check out, but many resources can now be accessed electronically by using your library card.
Many states have library systems that allow patrons in one city to utilize materials owned by another library in a different city. With apps such as OneDrive and Hoopla , users can gain access to thousands of digital materials, including books and media. These apps are typically compatible with the leading e-reader apps, such as Kindle , Kobo , and Libby . Also, libraries have become a central access point and technology hub for those lacking these resources at home, as Figure 1.28 shows. Nearly 96 percent of all rural public libraries offer free access to the internet for their cardholders. In all these ways, the digital revolution has altered the way libraries think about the services they provide.
Libraries can be a source of research that might otherwise be unavailable to you. For example, the popular genealogy site Ancestry.com has agreements with libraries to provide some of its exclusive material free of charge to users of the site’s library edition. Libraries also provide free access to other databases that are centered on business research, including LexisNexis , BizMiner , Business Source Complete , and IbisWorld . These databases provide a wealth of information that is not readily obtained with a simple internet search.
Web Applications
A web application is a software program that is not installed directly onto the user’s computer. Instead, the program and data associated with it are stored on the internet, and the application is accessed through a browser or app rather than through an installed program on the computer. In the past, users had to purchase a license key to install programs directly onto their computer. This takes up memory and storage space on the computer and presents limitations on updates to the program. The user would generally have to purchase the program on a regular basis to get the most updated version or purchase an upgrade. Web-based applications give users access to the most up-to-date version of the software while sometimes freeing up essential storage on the networks and allowing seamless collaboration between users in real time. Companies pay monthly or annual subscription fees for these programs, often based on the number of user licenses they want to purchase. Throughout this text, you will become familiar with the Google Workspace of products and Microsoft 365, so that you can develop basic computing skills for the work world.
E-commerce
Electronic commerce, or e-commerce , refers to conducting business transactions online—buying and selling goods or services in an online environment rather than in a traditional brick-and-mortar storefront. The first e-commerce transaction was in 1994, but it is helpful to think of e-commerce as a modern-day version of the catalog sales (Sears, JCPenney, Montgomery Ward) of times past, except that the ordering is done over a computer rather than over a telephone or by filling out a form and mailing it through the post office.
E-commerce transactions can occur between all customers in the marketing mix. In a business-to-business transaction, one business might purchase office supplies from another business. In a business-to-customer transaction, an individual purchases a product from a retailer online and has it delivered to their home. Consumer-to-consumer purchases can also be made through e-commerce—for example, when an individual purchases a product directly from another individual through a resale website.
E-commerce does not necessarily involve shipping the purchased items; for instance, you may purchase and download an electronic product, such as an e-book or music. E-commerce simply means that the purchase transaction occurs online rather than in person. Today, virtually all products or services can be purchased online. Some entrepreneurs have started exclusively online businesses with virtual storefronts and no physical inventory. Today, e-commerce makes up about 15 percent of all retail sales across the world, with over twenty million e-commerce sites worldwide, representing nearly $4 trillion in sales. E-commerce jobs are expected to reach nearly 500,000 by the end of the 2020s; it is predicted that by 2040, 95 percent of purchases will be through e-commerce.
Crowdfunding is a concept wherein many people contribute to fund a particular product launch or cause. Kickstarter is one such online platform where entrepreneurs can post their business idea and ask for contributions to make it happen. Some products have raised millions of dollars to fund their ideas. Pebbletime Smartwatch and the Coolertime Cooler garnered $20 million, $13.3 million respectively from Kickstarter donations.
The Cloud and Cloud Computing
Technological advances have made working remotely, or telecommuting , a possibility for many employees. In fact, one recent survey estimated that nearly 90 percent of U.S. employees would like to work remotely. Today, there are almost five million workers in the United States (nearly 40 percent of the U.S. workforce) who telecommute. Since 2015, the number of businesses that have allowed telecommuting has increased over 40 percent. Even for those who do not telecommute full time, access to the internet and such technologies as cloud computing in the workplace enable many employees to work from home at least once per month, with nearly 50 percent doing so once a week.
With cloud computing many of the resources that were traditionally stored on individual computers, including software programs, data management and storage systems, and networking tools, are moved to internet servers. This technological advance was prompted by the need to store large amounts of information and data and to enable collaboration by individuals across the world. The resources and their associated data are stored in a data center that is managed by a cloud service provider (CSP) . The benefits of cloud computing are that it can handle larger amounts of data than any physical storage device can, and it also allows users to access their data from any computer, no matter the location, and from any device, as Figure 1.29 illustrates.
The cloud is the term used to describe servers that are located at different locations and that are accessed via the internet. These servers are housed in data centers to provide storage and computer processing operations. The term cloud was first used in 1996 by a researcher at Compaq , and the first cloud computing service was Amazon Web Services (AWS) , which launched in 2002 as a public cloud system. The cloud offers some distinct cost advantages to businesses. Companies can save money by not having to constantly upgrade individual users’ storage capacity, and they can lower their IT costs because the subscription fee for use of the cloud service includes many troubleshooting and technical assistance functions. When we use the cloud for storage, we no longer need to store and maintain CDs with backups of the system or flash drives to transport documents from one computer to another. Cloud computing increases the speed of computing and gives all users real-time access to information stored in the cloud. Use of the cloud allows greater security for information storage as well as speedy distribution of new software and software upgrades. Finally, the cloud offers flexibility that enables businesses to operate more efficiently.
The security of information stored in the cloud can be of concern, but due diligence by individual users and the company can mitigate these risks. Here are some basic steps for ensuring the security of information:
- Select a CSP that encrypts its data. Computers use the process of encryption to rewrite readable information into a code that can be deciphered only by using the key to the code, similar to solving a word puzzle that uses a secret code (see Figure 1.30). Encryption is an important step in ensuring the security of the information transmitted and stored in the cloud.
- Back up information regularly. Most CSPs will include this with the services they provide.
- Use strong passwords and change the passwords regularly. Some businesses will set up a system that requires a password change at set time intervals.
- Use two-factor authentication . This means that to access the system, you will need two pieces of identification, typically your username and password as well as one additional means of identification, such as an email to verify your identity, a code sent to your cell phone, or an answer to a personal question.
- Make sure your system is protected by antivirus/antimalware software. These programs prevent unauthorized attempts to gain access to the system.
- Avoid using public Wi-Fi access points to conduct critical business or personal transactions. Using public Wi-Fi exposes users to the potential for personal information to be compromised.
Cloud Computing in Business
Some companies set up a cloud-based intranet —a private network for internal company use. Unlike the internet, it is not available to the public and typically requires authorized users to enter a username and password. Many companies also require employees to make use of a virtual private network (VPN) to gain access to the company’s intranet when they are off-site.
The use of virtual private networks enables businesses to control who gains access to their computer network. Using cloud services can offer some of the same security advantages for business. Read this article on VPN and cloud computing to learn how the two are related and some differences between the two.
Many businesses today use cloud computing to manage their information technology needs. Through the cloud, businesses can more efficiently analyze, manage, and store data. They are able to deliver software to their employees on demand and make updates to programs more rapidly. Finally, cloud computing enables seamless collaboration between business units that may be located miles apart.
Three types of clouds are involved in cloud computing:
- The public cloud is managed by a CSP. All of their services are delivered via the internet, and they charge for their service. The resources are owned and maintained by the CSP. Microsoft Azure and IBM Cloud Services are examples of public cloud service providers.
- A private cloud is used within a single business or organization. Its resources, which are owned by the business and maintained within the organization, are stored on a private network, or the company can pay a third party to host the private cloud. With a private cloud, there are often restrictions on who can use it and what permissions are given to the users. Businesses that use sensitive information, such as financial institutions or health-care providers, prefer private clouds because they offer more security than a public cloud system.
- The final type of cloud system is a hybrid cloud —a blend of public and private. Some resources are utilized through a public cloud and others are secured through a private cloud.
Cloud Computing for Personal Use
You are probably using the cloud already in your professional or personal life, even if you are unaware that you are doing so. For example, cloud computing is used behind the scenes for Google and Microsoft programs, so if you are using Gmail or Outlook , you are using the cloud. Likewise, if you use Google Photos to store family memories, you are using the cloud. And if your family members play video games, stream movies, or listen to music on the internet, they are more than likely using the cloud. The cloud is working behind the scenes with much of the work we do both personally and professionally. This is a natural outgrowth of advances in internet capabilities and computing power to enable us to manage information more efficiently, conveniently, and cost-effectively.
Internet of Things (IoT): Integration and Collaboration
The Internet of Things (IoT) refers to the extension of internet connectivity beyond computers, to enable the transfer of information between machines and other objects, people, and animals by connecting them to the internet in some way. With the IoT, the physical connects to the virtual. Today, many consumers seek out products that connect to the internet, and some simple adjustments enable many nontechnical, inanimate objects, from light bulbs to dishwashers, to be part of the IoT.
As businesses see the value of the additional data that is gathered through IoT, many companies are marketing these technologies to consumers to make their lives easier and to save money. Having a reminder to put the laundry in the dryer or having the house thermostat adjust automatically based on outside temperature is more than a novelty—these features can save time and money, allowing consumers to feel more secure, better equipped to handle life’s demands, and able to focus more on their pleasures in life. Businesses, too, can realize distinct improvements using real-time data and analytics, performance tracking, inventory/cost controls, and the automation of simple tasks. These capabilities can also allow businesses to adapt to challenging times.
COVID-19 drastically affected in-person business and services, many of whose owners found themselves struggling just to keep their businesses afloat. Some businesses chose to start offering their products or services online while some began or greatly enhanced their delivery operations. Others decided to close their business in the short term. Some businesses, such as Spotify and Netflix , put more resources into creating original content (podcasts, movies, series shows) rather than relying primarily on the sale of ads as a major revenue stream. Small restaurants offered delivery services and meal subscription services to keep their business thriving even during the pandemic. And larger corporations found that remote work allowed their employees to stay healthy while still meeting the needs of the business.


5.1: Federal level
The Federal Bureau of Prisons was established in 1930 to provide more progressive and humane care for federal inmates, to professionalize the prison service, and to ensure consistent and centralized administration of the 11 Federal prisons in operation at that time. Today, the Bureau includes 121 institutions, 6 regional offices, a Central Office (headquarters), and 26 offices that oversee residential reentry centers. The regional offices and Central Office provide oversight and administrative support to the institutions and offices. The Bureau is responsible for the care and custody of more than 208,000 federal inmates, as of spring 2015.1 About 81 percent of these inmates are confined in federal correctional institutions or detention centers, and the remainder are held in secure privately managed or community-based facilities and local jails under contract with the Bureau. The Bureau protects society by confining offenders in prisons and community-based facilities that are safe, humane, cost-efficient, and appropriately secure, and by providing inmates with programs and services to assist them in becoming proactive law-abiding citizens when they return to their communities. The Bureau’s most important resource is its staff. All Bureau staff are expected to conduct themselves in a manner that creates and maintains respect for the agency, the Department of Justice, the Federal Government, and the law.
The Bureau operates institutions at four security levels (minimum, low, medium, and high) and has one maximum-security prison for the less than one percent of inmates who require that level of security. It also has administrative facilities, such as pretrial detention centers and medical referral centers that have specialized missions and confine offenders of all security levels. The Bureau also classifies its institutions based on the level of medical services readily available, as care levels 1-4. The characteristics that help define the security level of an institution are perimeter security (such as fences, patrol officers, and towers), level of staffing, internal controls for inmate 3 movement and accountability, and type of living quarters (for example, cells or open dormitories).
The Bureau’s graduated security and medical classification levels allow staff to assign an inmate to an institution in accordance with his/her individual needs. Thus, inmates who can function with relatively less supervision, without disrupting institution operations or threatening the safety of staff or other inmates, can be housed in lower security level institutions. Regardless of the specific discipline in which a staff member works, all employees are “correctional workers first.” This means everyone is responsible for the security and good order of the institution. All staff are expected to be vigilant and attentive to inmate accountability and security issues, to respond to emergencies, and to maintain a proficiency in custodial and security matters, as well as in their particular job specialty. This approach allows the Bureau to operate in the most cost-effective manner with fewer correctional officers and still maintain direct supervision of inmates.
The Bureau relies on security technologies to help ensure the safety of staff and inmates. Recently new technologies have included whole body imaging devices to detect contraband (including cell phones) and sophisticated walk-through metal detectors, thermal fencing, and thermal camera sensors. These technologies have significantly reduced contraband. Additionally, the Bureau has provided staff additional equipment, such as oleoresin capsicum spray, to further enhance safety.
The Bureau’s philosophy is that preparation for reentry to society begins on the first day of incarceration. Accordingly, the Bureau provides many programs, designed to assign inmates and address their needs such as substance abuse treatment, mental health treatment, education, anger management, parenting and more. Prison work programs provide inmates an opportunity to acquire marketable occupational skills, as well as acquire a sound work ethic and habits. Medically able inmates are required to work some. For some individuals, this represents their first employment experience. Work assignments provide on-the-job training similar to what would be received in the community. For example, inmates work as clerks, landscapers, and electricians. Many work assignments are linked to vocational training programs and may lead to formal apprenticeships.
Near the end of their sentence, inmates participate in the Release Preparation Program, which includes a series of classes regarding daily living activities in the community including employment, banking, resume writing, job search strategies, and job retention. It also includes presentations by representatives from community-based organizations that help former inmates find employment and training opportunities after release. The Bureau helps inmates maintain ties with their family and friends through visiting, mail, email and the telephone.
The Bureau specifically encourages inmates to maintain and develop bonds with their children through parenting programs that include specialized activities such as day camps and workshops. The Bureau’s Inmate Transition Branch helps inmates prepare release portfolios that include a resume, education and training certificates and transcripts, diplomas, and other significant documents needed to secure employment. Many institutions hold mock job fairs to allow inmates to practice job interview techniques and expose community recruiters to the skills available among inmates.